Variable character printing apparatus



Sept. 23, 1969 YOW-JIUN HU 3,468,244

VARIABLE CHARACTER PRINTING APPARATUS Fild Oct. 13, 1966 6 Sheets-Sheet1 nvwswraz YOW J/U/V HU Sept. 23, 1969 vowu 3,468,244

VARIABLE CHARACTER PRINTING APPARATUS Filed Oct. 13, 1966 6 Sheets-Sheet2 m N a u no v 3%- g, n rl q? to Sept. 23, 1969 YOW-JIUN HU 3,468,244

VARIABLE CHARACTER PRINTING APPARATUS Filed Oct. 13, 1966 6 Sheets-SheetZ5 Sept. 23, 1969 YOW-JIUN HU VARIABLE CHARACTER PRINTING APPARATUS 6Sheets-Sheet 4 Filed Oct. 13. 1966 Sept. 23, 1969 YOW-J|UN I-IU VARIABLECHARACTER PRINTING APPARATUS 6 Sheets-Sheet 5 Filed Oct. 13, 1966 m 6ftI .v v NN n m d v QN n C J\ 8 u mN l a u S 6 u m l 5 -520 L mmlluullllhmulxmml I I I I i I I l I |||1 Se t. 23, 1969 YOW-JIUN HUVARIABLE CHARACTER PRINTING APPARATUS 6 Sheets-Sheet 6 Filed Oct. 13,1966 3,468,244 VARIABLE CHARACTER PRINTING APPARATUS Yow-Jiun Hu,Alexandria, Va, assignor to Farrington Business Machines Corporation,Springfieid, Va., a corporation of Massachusetts Continuation-impart ofapplication Ser. No. 401,273, Oct. 2, 1964, now Patent No. 3,280,739,dated Oct. 25, 1966. This application Oct. 13, 1966, Ser. No. 586,421

Int. Cl. B41f 3/20, 3/04, 1/04 U.S. Cl. 10199 13 Claims ABSTRACT OF THEDISCLOSURE An apparatus in a printing machine comprising a tray orprinting bed which is movable into printing and nonprinting positionsrelative to a printing path traversed by a platen mounted on theprinting machine. The movable tray includes type bars which areselectively positionable through a printing station on the tray. Thetray in the nonprinting position is loaded with a printing plate anddocument and the individual type bars are selectively positionedaccording to the particular transaction being accomplished. An alignmentmechanism for the type bars comes into play when the tray is moved inthe printing position. The tray is locked in the printing position untilan imprint is made and then the tray is released for return to thenonprinting position. One of several further features provides for anarrangement to automatically return the type bars to a reference datumposition on the tray when the tray itself is returned to thenon-printing position.

This invention relates to a device for printing indicia such as variablepositioning data on sales slips, documents or the like wherein the datais printed from individual printing devices positionable within themachine from the exterior thereof.

The present application is a continuation-in-part of my earliercopending application Ser. No. 401,273 filed Oct. 2, 1964, theimprovement comprising the combination of a movable printing stationapparatus comprising the selective positioning of variable data arrangedon the type bars.

The objects of this invention are to provide a printing device which issimple and economical in construction, which produces a clean cut anduniform printing with inexpensive plates, which operates convenientlyand with little effort, which is durable and reliable in use, and whichwill print various types of fixed and variable intermittently changedinformation.

Briefly, the device has a movable printing bed or tray to receive salesslips or the like, with selectively positionable longitudinallyextending type bars and one or more seats for printing plates which inthe present embodiment is shown in combination with a carriage assemblycomprising a curved platen selectively cut-out for printing only onetransverse line of data across the type bars. The tray is so arranged asto enable the machine to operate automatically for a single imprintcycle at a time, and allow a tray upon which the printing bed is locatedto be movably disposed relative to the carriage assembly for furtherconvenience. Further improvements provide for allowing the type bars onthe tray to be aligned accurately when the tray is moved into a printingposition and provide automatic reset of the type bars when the tray isreturned to an initial start position.

Although the variable positionable character mechanism employed on amoving tray is shown in the illustrated embodiment to be utilized incombination with the curved platen assembly shown herein, it isunderstood, of course,

atent O "ice that other types of manual or powered platen assembliesmight be employed in combination therewith.

For the purpose of illustration, a typical embodiment of the inventionis shown in the accompanying drawings in which FIGURE 1 is an isometricview of the printing machine.

FIGURE 2 illustrates a section of the machine taken on the line 2-2 ofFIGURE 1 with the tray 51 having been pushed inwardly.

FIGURE 3 is a section of the machine taken on the line 3-3 of FIGURE 2with the carriage assembly 31 having been rocked into a positionslightly displaced from the printing bed.

FIGURE 4 shows a cut-away fragmentary view disclosing the type barassembly in greater detail and also illustrating the lowering of guidemeans 45 and rotation of carriage assembly 31.

FIGURE 5 is a bottom view of FIGURE 2.

FIGURE 6 illustrates a section of the printing machine taken on the line66 of FIGURE 2.

FIGURE 7 shows a top view of FIGURE 2 with the motor 24 removed.

FIGURE 8 is a schematic diagram relating to the movement of the carriageassembly 31.

FIGURE 9 shows a section of the type bar assembly taken on the line 99of FIGURE 5.

FIGURE 10 is an isometric enlarged view of the actuator arm 149partially shown in FIGURES 1, 5 and 9.

The embodiment herein shown for the purpose of illustration comprises aprinting machine having a base 21, see FIGURES l and 2, with anupstanding wall member 22 to which a rigid plate 23 is secured formounting a power unit generally indicated at 24, which power unit may beof the electric or pneumatic type. The drive shaft 25 of the power unitis directly connected to an eccentric shaft 26 supported at one end bywall member 22 and at its other end by a wall member 27 which is spacedparallel with and attached to wall member 22 by way of wall separators28 and 29.

A carriage assembly generally referred to as 31, comprises a rocker arm32 and a bushing 33 having been force fitted within a circular openingin the rocker arm 32, whereby the opening defined by the bushing 33 isadapted to be loosely fitted about the eccentric shaft 26, for easyrotation of the arm thereabout. Spacers 34 are provided to prevent therocker arm from lateral movement along the eccentric shaft. A platen 35is snugly mounted on the bottom of rocker arm 32 by providing guidegrooves 36 in the arm to be compatible with an extension 37 of theplaten, thus allowing the platen to be easily replaced. The platen couldbe of metal, plastic or of some porous material impregnated with inksuch as the platen disclosed in U.S. Patent No. 2,620,730, and ifdesired the printing surface of the platen could be partially relievedas shown in FIGURE 4 forming an extension finger 38' so that anyunwanted information on a printing plate or else where in the printingfield, would not be recorded. The printing surface 38 of the platen 35has a curved configuration to be hereinafter disclosed in more detail.

In a preferred embodiment of the present invention, a bearing 39 (seeFIGURES 2-4) integral with a plate member 41 is attached above thesurface of platen by screw means 42 to a recessed portion 43 of thecarriage assembly for limited movement in a vertical slot 44 formed by aguide member 45, which guide member is attached to a screw 47 andsecured to an identation 4 6 in wall member 27 by the frictionalcoaction of screw 47 and guide member 45 with the wall 27 when the screwis tightened thereto. Upon loosening of screw 47, the screw and attachedguide member 45 may be lowered toward the base 21 by way of elongatedslot 48 as illustrated in 3 FIGURE 4, thereby freeing the carriageassembly 31, when displaced at substantially its furthermost positionfrom a printing bed, from the guide slot 48, thus allowing the carriageassembly 31 to be manually rotated by facilitating maintenance of themachine in replacement or cleaning of the platen member 35. If desired,the ends of the platen may be additionally secured to the rocker 32 byway of a flathead screw 49.

Beneath the carriage assembly 31 and mounted on base 21 is tray 51,wherein there is positioned an anvil 52 defining a portion of a printingbed disposed to receive an embossed customer identification token orprinting plate 53. There is also provided adjacent anvil 52, a printingplate 54 for afiixing thereto station identification information such asthe station address, assigned number for recording purposes, etc.whereby both, the identification token 53 on anvil 52 and printing plate54, are employed to support a document or sales slip 55 upon which animprint is to be made. The identification token 53 may be of theconstruction shown in Patents 2,620,729 or 3,034,- 430, being formedwith raised characters. To one side of printing plate 54 there islocated a variable numbering wheel 56 for recording of additionalinformation such as the date of a transaction. The rim portions 57 and58 of tray 51 are utilized for properly positioning the sales slip 55within the tray, whereas on either side of anvil 52, the yieldablebiased members 59 and rim 61 are employed for properly locating theidentification token 53. The far side 62 of anvil 52 is indentedallowing the identification token to be readily tipped for convenientremoval from the printing machine. It is noted that the left band edge57 of tray 51 may be extended outwardly from the tray by way ofextensible rods 63, as shown in FIGURE 1, for accommodating large sizesales slips.

As disclosed in FIGURE 3, tray 51 is movable with respect to thecarriage assembly 31 of the imprinting ma chine via a pair of parallelguide tracks 64 in base 21 receiving the protracted portions 65 of tray51. The rear of the imprinting machine, as illustrated in FIGURES 2 and7, is provided with a compression spring 66 wound about a holder 67mounted on the tray 51 by angle support 68, the spring being guided inan indentation 69 of the base 21 and the free edge of the spring beingfixed to the base by screw 71. The spring 66 is biased in the directionshown by the arrow to force the tray 51 outwardly in a documentreceiving or removal position. To limit the outward movement of the traya recess 72 is terminated at point 73 in the tray 51 to engage the capof screw 71 as shown in FIGURE 5. In tray 51 and complimentary with theangled underside of anvil 52 is a wedge 74 having a width which issubstantially narrower than that of anvil 52, which anvil occupies thefull width of the cut-out in tray 21 within which it is seated. Abuttingthe front end of wedge 74 there is shown in FIGURE an anvil supportscrew 75 threadedly transferable through passageway 76 in a stair-likemember 77 which is pivotable about the screw 78 fixed to tray 51. It isreadily observed that by adjusting the anvil support screw 75 abuttingwedge 74, anvil 52 may be raised or lowered to regulate the distance ofthe identification token 53 from the platen 35 to achieve a proper printquality on the document 55.

It is additionally noted that if, for some reason, the carriage assembly31 becomes jammed during printing, the operator by rotation of thestair-like member 77 about the pivotable screw 76 to the position 77 (asshown in FIGURE 1), may disengage the anvil support screw 75 from thewedge 74 allowing anvil 52 to be lowered for relieving the jam. Thestair-like member 77 is held in its normal position by frictionalengagement with wedge 74.

The motor 24 is connected to a normally open snapaction switch 79, asillustrated in FIGURE 1, which switch circuit is closed to activatemotor 24 when biased pin 81 is forced inwardly as shown in FIGURE 7, thesnap-action switch being electrically connected to a further switch 82,thence to a voltage source by way of leads 83, Pin 81 of snap-actionswitch 79 is situated so as to be forced inwardly by the action againstspring 86 of the angle support 68 on tray 51 when the tray is pushedinwardly towards the carriage assembly 31. The apparatus which locks thetray 51 after it has been pushed forward for an imprinting function andalso releases the tray thereafter for removal of the printing plate 53and document 55, is shown in FIGURES 2 and 6, comprising a pear-shapedcam 84 fixed to the eccentric shaft 26 to be rotatable therewith as thecarriage assembly is rocked about the eccentric shaft 26, whereby thetop portion of pear-shaped cam 84 will be at its further-most positionfrom the printing bed. A slide 85 slidable up and the side of wallmember 22 by way of an elongated slot 86 is guided through the rigidplate 23. The top of the slide 85 has a rod 87 protruding therefrom tocoact with the pear-shaped cam 84 for vertical up and down movement ofthe slide whereas the bottom of slide 85 is integral with a latch 88adapted to coact with a catch 89 when dropped as cam 84 rotates, forlocking the tray 51 after having been pushed forward in a ready forimprint position as illustrated in FIGURE 2. The catch 89 is adjustablewithin a cut-out 91 in the tray 51 by means of a screw 92, so that whilethe tray 51 is locked it will, via angle support 68, maintain thedepression of pin 81 of snap-action switch 79 through spring 80, tocontinuously activate motor 24 and thus the rocking of carriage assembly31 for accomplishing an imprint from identification token 53, printingplate 54 and date wheel 56 onto document 55. It is noted that cam 84 isso shaped that, in one position after a complete revolution of eccentricshaft 26 or a complete imprinting cycle of carriage assembly 31, it willact upon rod 87 to lift slide 85 and therefore lift latch 88 releasingthe tray 51 when the platen carriage 31 has been rocked about eccentricshaft 26 to be in its uppermost position relative to the printing bed.Upon lifting latch 88 from engagement with catch 89, the rewinding ofbiased spring 66 will force tray 51 outwardly, thus deactivating motor24 until the tray is again pushed inwardly.

The rocking motion of the carriage assembly 31 as it is driven about theeccentric shaft 26 via drive shaft 25, is clearly shown in the schematicdrawing of FIGURE 8 wherein the eccentric shaft is replaced by anequivalent crank, whereby the particle 93 represents the center of thedrive shaft 25, particle 94 represents the center of the offset portionof eccentric shaft 26 which portion is driven about drive shaft 25 in acircle denoted by the dashed circle 95, and particle 96 represents thecenter of the hearing 39 which is fixed to the carriage assembly 31 andguided for vertical sliding movement in the guide member 45 as thecarriage assembly 31 is rocked. The particles are connected by linkagemembers, which when driven around one complete revolution of circle willdenote the various positions of the platen 35 relative to a printing bed97. It will be observed that in the present embodiment only one quarterof a complete revolution of eccentric shaft 26 is employed forperforming an imprint whereby the platen 35 contacts the document andidentification token on printing bed 97. It has been found in practicethat it is desirable to achieve as true a rolling action as possible,and thus fixed bearing 39 may be easily positioned to achieve such aneffect.

Situated on the right hand side of the tray, as illustrated in FIGURES 1and 4, are a series of type heads 121, 122, 123, 124 and 125 each havingtype element 0 through 9 thereon. The type heads are respectivelymounted on a series of selectively settable type bars 126, 127, 128, 129and 130, each of which bars is longitudinally slideable in a directionparallel to the tray movement, and at least slideable for selectivelypositioning any one of the several type elements within an area adjacentthat of anvil 52. The type bars are individually movable through oneeach of a plurality of tabulator knobs 131 secured thereto by way ofoiIset extension arms 132.

The type bars ride on the upper surface of tray 51 and are separatedfrom one another, adjacent opposite ends, by spacers 132', preferably ofnylon, which spacers are protruded from a fixed body within the tray andwhich spacers additionally assist in guiding the type bars Within eachof a plurality of well defined paths. Located at each of the oppositeends of the tray is one of a pair of brackets 133 enclosing all of thetype bars and holding them together for more accurate positioning, andfurther preventing the type bars from substantial movement in thevertical direction. Rollers 134 are mounted on a shaft 135 at the top ofthe brackets 133 to provide an enhanced sliding movement of the typebars When handled by an operator.

As may be observed from FIGURE 9 the bottom exterior surface of eachtype bar is formed with a plurality of notches 136 having a selectedrelationship relative to a corresponding type element positioned on theupper surface of the corresponding type bar. Below the type bars are aplurality of detents 137 each having right angle configuration and allmounted to be pivotable about a common shaft 138. As illustrated inFIGURE 9 a plurality of leaf springs 139 separately but lightly bias inan upward direction each detent 137 in a clockwise direction about thepivot shaft 138 to bring the detent end into engagement with a notch136. By way of such a resilient detent action each type bar isselectively and correctly positioned or registered. As may be seen inFIGURE 9, to visually ascertain where the printing field for the typeelements lies relative to platen element 38, a locator member 141 havinga cut-out window 142 is provided. The locator member may have writtendata thereon for denoting cents and dollars or any other type of similarinformation which might aid the opeartor.

Referring back to FIGURES 5 and 9 there is shown a separate rod 143extending downwardly from each of the type bars at their forward ends.The bottom portion of each rod 143 is tied to the rearward end of thetray by one of a plurality of tension springs 144. Running beneath allof the detents 137 in a transverse direction, is a single alignment bar145 adapted for movement in the vertical direction, and being looselyheld within a groove 146 in tray 51 by way of the springs 144, whichsprings pass through a series of openings 147 formed within thealignment bar, a separate opening being formed for each of thelongitudinally extending springs 144. The tension on springs 144 is suchthat should a detent 137 be engaged with a notch 136, it will not beable to overcome the force of leaf spring 139 acting up to maintain suchengagement.

Situated directly above detents 137 and also running in a transversedirection thereto, is a reset lever 148 in the shape of a cylinderbisected in its longitudinal axis as illustrated in FIGURE 10. The resetlever is extended to the side of the tray 51 through a circular slot 150where it is secured to a vertical movable oblong shaped actuator arm 149mounted at a right angle relative to reset lever 148 as may also be seenfrom FIGURE 4. Pivotably mounted slightly in from one end of theactuator arm is a finger 151 extending downwardly beneath the lowerexterior surface of actuator arm 149 and biased by spring 152 towardthat same end of the actuator arm to abut an outward protruding wall 153of actuator arm 149, yet finger 151 is no positioned that the finger maybe rotated against the spring tension about forty to ninety degrees inthe direction 17 indicated by the arrow M. In operation, should actuatorarm 149 be moved upwardly, it will in turn rotate the reset lever 148 inthe P direction to collectively force the detents 137 downwardly againstsprings 139 and away from engagement with the notches 136 in the typebars allowing the force on the forward end type bars from springs 144 tobe dominant and reset the type bars.

As may be observed from FIGURE 4, a raised platform 154 having angularshaped edges 155 is seated on the base 21 at an area over which is to betraversed by the traveling tray 51. More specifically, when the tray hasbeen completely pushed into printing position on the base, the platform154 will lie under that area occupied by the alignment bar 145, and dueto its positioning will cause the alignment bar to be raised byengagement therewith into contact with all of the detents 137 forcingthe same into engagement with notches 136 to lock the type bars andprevent vertical movement of the type bars while the tray remains in theprinting position.

On the side of the base 21, adjacent the type bar area and dlrectly inline with the travel of the actuator arm 149 is a trip bar 156. Theheight of the trip bar from the base 21 is such that while the tray isinitially pushed forward, it Will cause the finger 151 to be rotated inthe M direction (see FIGURE 10), however, the trip bar will not contactthe actuator arm spaced therefrom and thus will not cause :he same to bemoved at that stage of the machine opera- In operation of the abovedescribed device, an identification token will be inserted on anvil 52and thereafter a document 55 will be placed upon the tray surface whilethe tray is in an open position as disclosed in FIGURES 1 and 4. It willbe assumed that the tabulator knobs 131 have been reset to theirreference position as shown in FIGURES 1 and 4 as reflected by thewindow 142. The machine operator will then individually position thetype bars to selected settings in accordance with a specifictransaction, which combined settings would be visuallynndicated by thesetting window 142. During this operat1on the detents will be forced inand out of the notches 136 due to the action of leaf springs 139 tocause a clicking l1ke sound which will audibly assure the operator ofhaving accurately positioned the type setting. Due to the vibrationstransferred by way of the snapping detents, the operator willadditionally feel when a detent 137 has been forced into notch 136.Then, the tray 51 will be pushed inwardly against wound spring 66 untilthe tray 1s forced against spring to depress pin 81 thus activating themotor 24 which drives the eccentric shaft 26. As the tray is pushedinwardly finger 151 will contact trip bar 156 and be pivoted in the Mdirection while the actuator arm 149 remains stationary relative to tray51. Further inward movement of the tray into printing position willcause the alignment bar to be raised vertically as it rides up theraised platform 154. In such a raised position the top of the alignmentbar 145 will contact all of the detents 137 and align and lock then fromvertical movement into engagement within the notches which they werepreviously set to by the operator. As the eccentric shaft 26 is rotated,pear-shaped cam 84 will be displaced from its position shown in FIGURE6, thereby allowing latch 88 to be dropped for engagement with catch 89,as illustrated in FIGURE 2, to hold the tray 51 inwardly against motoractivating pin 81 and simultaneously maintaining the printing bed inalignment for imprinting upon document 55 by carriage assembly 31. Asthe carriage assembly is directed in the clockwise direction, platen 35is brought into a rocking type contact with the sales slip 55 on theprinting bed and platen element 38 and 38' will only contact thatportion of the sales slip overlying the type numerals located at thewindow 142 and the identification token to produce an optimum qualityimprint transfer onto the sales slip 55 from identification token 53 andthe selected type numerals. Upon completion of one revolution of theeccentric shaft 26 and after the accomplishment of an imprint, thepear-shaped cam 84 will raise latch 88 as shown in FIGURE 6 allowing theforce of wound spring 66 to force the tray 51 outwardly for documentremoval and deactivation of motor 24.

As the tray moves outwardly the locking bar 145 will slide off theraised platform 154 and therefore lower the alignment bar from lockingengagement With the detents 137 and the type bars. Further outwardmovement of the tray will cause the finger 151 to contact the trip bar156 and since the finger will become locked into its lower position byabutting action with wall 153 (see FIGURE 10) the entire actuator arm149 will be raised due to its positioning and thus rotate reset lever148 in the P direction to force the detents 137 against springs 139 andout of contact with notches 136 in the type bars. Simultaneously, thetensioned springs 144 will draw the type bars back into their referenceposition, for subsequent settings during the next printing operation tobe accomplished.

In a further feature, while tray 51 is in its document receivingposition and motor 24 is deactivated, the guide member 45 may beloosened by means of screw 47 and thus lowered away from hearing 39.Thereby, due to the unique construction and arrangement, one maymanually rotate the carriage assembly 31 about eccentric shaft 26, asshown in FIGURE 4, for easy and quick cleaning or replacement of theplaten 35.

Although the above printing mechanism is shown to be utilized with apower unit 24, it may be readily operated manually by simply providingan operating handle 98 for attachment to the bolt terminal end of theeccentric shaft 26 as shown in FIGURE 4.

It should be understood, of course, that the foregoing disclosurerelates to only a preferred embodiment of the invention and thatnumerous modifications or alterations may be made therein withoutdeparting from the spirit and scope of the invention, it is desiredtherefore, that only such limitations be placed on the invention as areimposed by the prior art and as set forth in the appended claims.

It is claimed:

1. A printing apparatus comprising a stationary base, a tray having aprinting station adapted to support a portable printing plate thereat, ahead assembly fixedly supported on said base and including a printinghead having a platen adapted for movement through a printing pathrelative to the base, a plurality of type bars mounted in adjacentrelation on said tray, selector means connected to said type bars forindividually moving each of said type bars to bring any one of aplurality of type characters to be printed into position at the printingstation, means for moving said tray along the base into stable printingand non-printing positions, said printing station adapted to lieadjacent said printing path when the tray is in the printing positionenabling the platen to print data at the printing station on a forminterposed between the tray and the head assembly, and said printingstation adapted to be spaced from the printing path when the tray is inthe non-printing position.

2. Apparatus according to claim 1 including aligning means adapted formovement into engagement with said type bars for accurately aligning thetype characters on the type bars with one another prior to imprinting,said aligning means normally disengaged from said type bars when thetray is in the non-printing position, and actuating means for movingsaid aligning means into aligning engagement with said type bars whenthe tray is moved into the printing position.

3. Apparatus according to claim 1 including separate detent meansadapted for yielding engagement with each type bar providing properprinting registration of each type character prior to imprinting thecharacter, aligning means adapted for movement into engagement with saiddetent means to provide a positive engagement with the type bars foraccurately aligning the type characters on the type bars, said aligningmeans normally disengaged from said detent means, and actuating meansfor moving said alignment means into engagement with the detent meanswhen the tray is moved into the printing position.

4. Apparatus according to claim 1 including means for releasably lockingthe tray against movement in the printing position until the platen hastraversed the printing station, and means for biasing the tray into thenonprinting position after the platen has traversed the printingstation.

5. A printing apparatus comprising a base, a tray having a printingstation, a head assembly supported on said base and including a printinghead having a platen adapted for movement over a printing path relativeto the base, a plurality of type bars mounted in adjacent relation onsaid tray, selector means connected to said type bars for individuallymoving each of said type bars to bring any one of a plurality of typecharacters to be printed into position at the printing station, meansfor moving said tray relative to the base into printing and nonprintingpositions, said printing station adapted to lie adjacent said printingpath when the tray is in the printing position enabling the platen toprint data at the printing station on a form interposed between the trayand the head assembly, said printing station adapted to be spaced fromthe printing path when the tray is in the non-printing position,aligning means adapted for movement into engagement with said type barsfor accurately aligning the type characters on the type bars with oneanother prior to imprinting, said aligning means normally disengagedfrom said type bars, actuating means for moving said aligning means intoaligning engagement with said type bars while the tray is in theprinting position, and means for releasably locking said tray againstmovement in the printing position until the platen has traversed theprinting path.

6. Apparatus according to claim 5 including means for normally biasingsaid tray into the non-printing position, means for releasing said trayfrom said locked position when a printing operation is completedallowing said tray to be urged into the non-printing position.

7. A printing apparatus comprising a base, a tray having a printingstation, a head assembly supported on said base and including a printinghead having a platen adapted for movement over a printing path relativeto the base, a plurality of type bars mounted in adjacent relation onsaid tray, selector means connected to said type bars for individuallymoving each of said type bars to bring any one of a plurality of typecharacters to be printed into position at the printing station, meansfor moving said tray relative to the base into printing and non-printingpositions, said printing station adapted to lie adjacent said printingpath when the tray is in the printing position enabling the platen toprint data at the printing station on a form inter-posed between thetray and the head assembly, said printing station adapted to be spacedfrom the printing path when the tray is in the non-printing position,separate detent means adapted for yielding engagement with each type barproviding proper printing registration of each type character prior toimprinting the character, the indicia marked control panel on said trayalongside the area where said type bars are slidable, said selectormeans having a reference datum position relative to said control panel,and means for automatically returning said selector means from a pre-setcondition to their reference datum position when the tray is moved fromits printing position to its nonprinting position.

8. Apparatus according to claim 7 wherein said automatic return meanscomprises spring means for acting on said type bars to normally bias theselector means to the reference datum position said spring means beingefiective only when the detent means does not engage the type bars.

9. Apparatus according to claim 8 including trip means adapted todisengage said detent means from the type bars when the tray is movedfrom the printing position to the non-printing position.

10. Apparatus according to claim 8 wherein said spring means is furtheradapted to provide a uni-directional resilient mount for the aligningmeans.

11. A printing apparatus comprising a base, a tray having a printingstation, a head assembly supported on said base and including a printinghead having a platen adapted for movement over a printing path relativeto the base, a plurality of type bars mounted in adjacent relation onsaid tray, selector means connected to said type bars for individuallymoving each of said type bars to bring any one of a plurality of typecharacters to be printed into position at the printing station, meansfor moving said tray relative to the base into printing and non-printingpositions, separate positioning means for yielding engagement with eachtype bar providing proper printing registration of each type characterprior to imprinting, aligning means adapted to provide positiveengagement of said positioning means with said type bar for accuratelyaligning the type characters on the type bars with one another prior toimprinting, said aligning means normally disengaged from the type bars,actuating means for moving said aligning means into positive engagementwith the positioning means when the tray is moved into the printingposition, means for releasably locking the tray against movement in theprinting position until the platen has traversed the printing path,means for normally biasing said tray into the non-printing position, andmeans for releasing said locking means after the platen has traversedthe printing path allowing the tray to be urged by the biasing meansinto the non-printing position.

12. Apparatus according to claim 11 including a reference datum positionfor said selector means, means for returning said selector means from apre-set condition to their reference datum position comprising springmeans acting on said type bars adapted to normally bias the selectormeans to the reference datum position when the positioning means doesnot engage the type bars, and trip means for disengaging the positioningmeans from the type bars when the tray is moved from the printingposition to the non-printing position.

13. Apparatus according to claim 12 wherein only one type character oneach type bar can be moved to be placed at the printing station at anyone time, and said platen has a selected configuration adapted to causean imprint on a document interposed between the type bars and the headassembly only at the printing station.

References Cited UNITED STATES PATENTS 1,305,778 6/1919 Cushing et a1.101-269 2,344,675 3/1944 Burts 346-58 3,058,416 10/1962 Grant et al101-269 3,138,091 6/1964 Maul 101-269 X 3,170,390 2/1965 Wagner 101-90 X3,279,369 10/1966 Wight 101-269 3,280,739 10/1966 Hu 101-297 WILLIAM B.PENN, Primary Examiner US. Cl. X. R. 101-45, 269, 297, 407

